[v3,2/6] eal: oops handling API implementation

diff --git a/lib/eal/unix/eal_oops.c b/lib/eal/unix/eal_oops.c
index 53b580f733..a480437f23 100644
--- a/lib/eal/unix/eal_oops.c
+++ b/lib/eal/unix/eal_oops.c
@@ -2,35 +2,194 @@ 
  * Copyright(C) 2021 Marvell.
  */
 
+#include <inttypes.h>
+#include <signal.h>
+#include <ucontext.h>
+#include <unistd.h>
 
+#include <rte_byteorder.h>
+#include <rte_log.h>
 #include <rte_oops.h>
 
 #include "eal_private.h"
 
-void
-rte_oops_decode(int sig, siginfo_t *info, ucontext_t *uc)
+/* It is not safe to call rte_log from signal handler due to the fact the
+ * malloc pool may be corrupted and rte_log uses malloc.
+ */
+#define oops_print(...) fprintf(stderr, __VA_ARGS__)
+
+static const int oops_signals[] = {SIGSEGV, SIGBUS, SIGILL,
+				   SIGABRT, SIGFPE, SIGSYS};
+
+struct oops_signal {
+	bool enabled;
+	struct sigaction sa;
+};
+
+static struct oops_signal signals_db[RTE_DIM(oops_signals)];
+
+static void
+back_trace_dump(ucontext_t *context)
+{
+	RTE_SET_USED(context);
+}
+static void
+siginfo_dump(int sig, siginfo_t *info)
+{
+	oops_print("PID:           %" PRIdMAX "\n", (intmax_t)getpid());
+
+	if (info == NULL)
+		return;
+	if (sig != info->si_signo)
+		oops_print("Invalid signal info\n");
+
+	oops_print("Signal number: %d\n", info->si_signo);
+	oops_print("Fault address: %p\n", info->si_addr);
+}
+
+static void
+mem32_dump(const void *ptr)
+{
+	const uint32_t *p = ptr;
+	int i;
+
+	for (i = 0; i < 16; i++)
+		oops_print("%p: 0x%x\n", p + i, rte_be_to_cpu_32(p[i]));
+}
+
+static void
+stack_dump_header(void)
+{
+	oops_print("Stack dump:\n");
+	oops_print("----------\n");
+}
+
+static void
+code_dump_header(void)
+{
+	oops_print("Code dump:\n");
+	oops_print("----------\n");
+}
+
+static void
+stack_code_dump(void *stack, void *code)
+{
+	if (stack == NULL || code == NULL)
+		return;
+
+	oops_print("\n");
+	stack_dump_header();
+	mem32_dump(stack);
+	oops_print("\n");
+
+	code_dump_header();
+	mem32_dump(code);
+	oops_print("\n");
+}
+static void
+archinfo_dump(ucontext_t *uc)
 {
-	RTE_SET_USED(sig);
-	RTE_SET_USED(info);
 	RTE_SET_USED(uc);
 
+	stack_code_dump(NULL, NULL);
+}
+
+static void
+default_signal_handler_invoke(int sig)
+{
+	unsigned int idx;
+
+	for (idx = 0; idx < RTE_DIM(oops_signals); idx++) {
+		if (oops_signals[idx] != sig)
+			continue;
+		/* Skip disabled signals */
+		if (!signals_db[idx].enabled)
+			continue;
+		/* Replace with stored handler */
+		sigaction(sig, &signals_db[idx].sa, NULL);
+		kill(getpid(), sig);
+	}
+}
+
+void
+rte_oops_decode(int sig, siginfo_t *info, ucontext_t *uc)
+{
+	oops_print("Signal info:\n");
+	oops_print("------------\n");
+	siginfo_dump(sig, info);
+	oops_print("\n");
+
+	oops_print("Backtrace:\n");
+	oops_print("----------\n");
+	back_trace_dump(uc);
+	oops_print("\n");
+
+	oops_print("Arch info:\n");
+	oops_print("----------\n");
+	if (uc)
+		archinfo_dump(uc);
+}
+
+static void
+eal_oops_handler(int sig, siginfo_t *info, void *ctx)
+{
+	ucontext_t *uc = ctx;
+
+	rte_oops_decode(sig, info, uc);
+	default_signal_handler_invoke(sig);
 }
 
 int
 rte_oops_signals_enabled(int *signals)
 {
-	RTE_SET_USED(signals);
+	int count = 0, sig[RTE_OOPS_SIGNALS_MAX];
+	unsigned int idx = 0;
 
-	return 0;
+	for (idx = 0; idx < RTE_DIM(oops_signals); idx++) {
+		if (signals_db[idx].enabled)
+			sig[count++] = oops_signals[idx];
+	}
+	if (signals)
+		memcpy(signals, sig, sizeof(*signals) * count);
+
+	return count;
 }
 
 int
 eal_oops_init(void)
 {
-	return 0;
+	unsigned int idx, rc = 0;
+	struct sigaction sa;
+
+	RTE_BUILD_BUG_ON(RTE_DIM(oops_signals) > RTE_OOPS_SIGNALS_MAX);
+
+	sigemptyset(&sa.sa_mask);
+	sa.sa_sigaction = &eal_oops_handler;
+	sa.sa_flags = SA_RESTART | SA_SIGINFO | SA_ONSTACK;
+
+	for (idx = 0; idx < RTE_DIM(oops_signals); idx++) {
+		/* Get exiting sigaction */
+		rc = sigaction(oops_signals[idx], NULL, &signals_db[idx].sa);
+		if (rc)
+			continue;
+		/* Replace with oops handler */
+		rc = sigaction(oops_signals[idx], &sa, NULL);
+		if (rc)
+			continue;
+		signals_db[idx].enabled = true;
+	}
+	return rc;
 }
 
 void
 eal_oops_fini(void)
 {
+	unsigned int idx;
+
+	for (idx = 0; idx < RTE_DIM(oops_signals); idx++) {
+		if (!signals_db[idx].enabled)
+			continue;
+		/* Replace with stored handler */
+		sigaction(oops_signals[idx], &signals_db[idx].sa, NULL);
+	}
 }